A semiconductor testing apparatus for conducting a conduction test after stabilizing contact between probing pins and a wafer is provided. The semiconductor testing apparatus includes a heat transfer block which is contacted to the probing pins to adjust the temperature of the probing pins to a predetermined testing temperature before the probing pins are brought into contact with the wafer.
|
1. An apparatus for testing a test piece, comprising:
test bench for supporting the test piece while maintaining the test piece at a predetermined testing temperature; a heat transfer block which is brought into contact with a tip of a probing pin to adjust a temperature of the probing pin to the testing temperature.
19. A method for testing a semiconductor wafer by contacting a plurality of probing pins to the semiconductor wafer, comprising the steps of:
maintaining the wafer at a predetermined testing temperature; maintaining a heat transfer block at the testing temperature; contacting the tips of the plurality of probing pins to the beat transfer block until a temperature of the plurality of probing pins reaches the testing temperature; and contacting the plurality of probing pins to the wafer.
14. A semiconductor testing apparatus for testing a semiconductor wafer, comprising:
a test bench for supporting the wafer; a probing card having probing pins which are brought into contact with the wafer; a heat transfer block which comes in contact with tips of the probing pins to adjust a temperature of the probing pins to a testing temperature, before the probing pins are brought into contact with the wafer; and a pressure absorber connected to the heat transfer block to maintain constant a pressure of contact between the probing pins and the heat transfer block.
2. The semiconductor testing apparatus according to
3. The semiconductor testing apparatus according to
4. The semiconductor testing apparatus according to
5. The semiconductor testing apparatus according to
6. The semiconductor testing apparatus according to
7. The semiconductor testing apparatus according to
8. The semiconductor testing apparatus according to
9. The semiconductor testing apparatus according to
10. The semiconductor testing apparatus according to
11. The semiconductor testing apparatus according to
12. The semiconductor testing apparatus according to
13. The semiconductor testing apparatus according to
15. The semiconductor testing apparatus according to
16.The semiconductor testing apparatus according to 17. The semiconductor testing apparatus according to
18. The semiconductor testing apparatus according to
20. The method according to
|
This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2002-153791, filed on May 28, 2002, the entire contents of which are incorporated herein by reference.
The present invention relates to a semiconductor testing apparatus for conducting a probing test on a semiconductor device or a substrate.
To effectively test a plurality of circuits formed on a semiconductor wafer, a probing card has 600 to 800 probing pins. Some of the probing cards manufactured presently have more than 1000 probing pins, adjacent ones of which have a spacing of 40 micrometers or less therebetween.
Since an electronic product, such as a cellular phone or a vehicle-mounted element, is used within a relatively wide temperature range, a circuit employed in such an electronic product is also tested over a wide range of temperatures. In a probing test, it is necessary to bring the probing pins into contact with the circuits substantially uniformly independently of a testing temperature.
Generally, in the step of manufacturing a semiconductor device, a probing test is conducted to test the conduction of a wafer. In the probing test, a plurality of probing pins are brought into contact with a plurality of corresponding pads formed on the wafer at a predetermined pressure. The various characteristics of the semiconductor device are measured in accordance with a probing test program.
The probing pins each elongate at a high test temperature and are shortened at a low test temperature. Accordingly, a pressure of contact between the pad and the probing pin varies, thus making the probing test unstable conventionally. The following will describe a conventional testing method by which an influence of a temperature variation in length of the probing pins is reduced.
When the probing test starts, the semiconductor testing apparatus 100 holds the chuck 90 at a predetermined testing temperature after heating with the heater 93 in step S91. In step S92, the semiconductor testing apparatus 100 moves the chuck 90 to a position which is separate downward from the probing card 91 by a predetermined spacing, for example, 500 micrometer. The chuck 90 radiates heat to pre-heat the probing pins 92. The pre-heating time ranges from a few minutes to several tens of minutes corresponding to the size of the probing card 91.
In step S93, the semiconductor testing apparatus 100 monitors the tip of the probing pin 92 and the upper surface of the wafer W using a camera (not shown) to simultaneously calculate the height of the chuck 90 when the tip of the probing pin 92 is brought into contact with the upper face of the wafer W.
In step S94, the semiconductor testing apparatus 100 moves the chuck 90 to the height thus calculated and brings the tip of the probing pin 92 into contact with the wafer W and then conducts a conduction test.
It is to be noted that since in the conventional semiconductor testing apparatus 100, the probing pin 92 is pre-heated indirectly in the position which is separate from the chuck 90, its temperature is saturated before the probing pin 92 reaches the testing temperature. The temperature of the probing pin 92, therefore, is lower than the testing temperature, or the temperature of the wafer W.
During the conduction test, the probing pin 92 is in contact with the wafer W, so that the probing pin 92 is heated by the wafer W to the testing temperature. Therefore, the probing pin 92 elongates further, thus decreasing the height of the tip thereof. Accordingly, a pressure of contact between the probing pin 92 and the wafer W varies greatly during the conduction test (step S95).
In the case of cooling the wafer W down to the testing temperature in order to conduct a probing test, on the other hand, a cooling circuit is used instead of the heater 93. In this case, the probing pin 92 is pre-cooled above the chuck 90 and so shrinks, thus increasing the height of the tip thereof. Furthermore, indirect pre-cooling causes the temperature of the probing pin 92 to become higher than that of the wafer W.
At the middle row in
At the upper row in
At the lower row in
In the conventional semiconductor testing apparatus 100, therefore, the pressure of contact between the probing pin 92 and the wafer W is unstable, thus likely to give rise to poor contact.
In a conduction test, the probing pin 92 is brought into contact with an electrode (pad) formed on the wafer W. If slippage (scrubbing quantity) of the probing pin 92 is large, the pin trace goes out of the relatively small electrode into a bonding region, thus deteriorating the strength thereof.
Japanese Laid-open Patent Publication No. Hei 5-152389 discloses a probing card and a test bench which have a heating body (or cooling body) buried therein. The heating body (or cooling body) causes the probing card (probing pin) and the test bench to have the same temperature. Accordingly, a fluctuation of a probing pin temperature owing to contact between the probing pin and the wafer is suppressed to suppress the elongation of the probing pin. It is necessary, however, to provide the heating body (or cooling body) for each probing card, so that costs are increased for testing and the manufacture of the semiconductor testing apparatus. Furthermore, the heating body in the probing card is electrified, so that test results may be affected by noise.
It is an object of the present invention to provide a semiconductor testing apparatus which can conduct a test stably on a semiconductor device. It is another object of the present invention to provide a semiconductor testing apparatus which can bring a probing pin into contact with a semiconductor device at a stable pressure.
To achieve the above object, the present invention provides an apparatus for testing a test piece. The apparatus includes a test bench for supporting the test piece while maintaining the test piece at a predetermined testing temperature, and probing pins which are brought into contact with the test piece. A heat transfer block is brought into contact with the probing pins to adjust a temperature of the probing pins to the testing temperature.
A further perspective of the present invention is a method for testing a semiconductor wafer by contacting a plurality of probing pins to the semiconductor wafer. The method includes maintaining the wafer at a predetermined testing temperature, maintaining a heat transfer block at the testing temperature, contacting the tips of the plurality of probing pins to the heat transfer block until a temperature of the plurality of probing pins reaches the testing temperature, and contacting the plurality of probing pins to the wafer.
Other aspects and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
The features of the present invention that are believed to be novel are set forth with particularity in the appended claims. The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:
The following will describe a semiconductor testing apparatus 10 according to a first embodiment of the present invention. As shown in
The tester 11 includes a measurement control unit 11a comprised of a main controller 13 and a measuring instrument 14. The wafer prober 12 includes a chuck controller 20, a probing card 21 having a plurality of probing pins, and a disc-shaped test bench, or chuck 22. On the chuck 22 is placed a test piece or a semiconductor wafer W on which electronic circuits such as an IC or an LSI are formed. The main controller 13 is connected to the chuck controller 20 through a control cable 23 and to the probing card 21 through a probing card control cable 24. The measuring instrument 14 is connected to the probing card 21 through an output cable 25. The output cable 25 is arranged, between the probing card 21 and the measuring instrument 14, as an interface for transferring data in a serial format in, for example, GP-IB communication.
The main controller 13 supplies a control signal through the control cable 23 to the chuck controller 20. The chuck controller 20 controls the chuck 22 in accordance with the control signal to move the chuck 22 so that the wafer W contacts with the probing pin 26 at a predetermined pressure.
The main controller 13 controls the probing card 21 through the probing card control cable 24. The probing card 21 supplies the measuring instrument 14 with a test result of the wafer W through the output cable 25. The main controller 13 evaluates the test result of the wafer W.
As shown in
The temperature controller 15 is connected to the wafer prober 12 through a control cable 31. The temperature controller 15 generates a temperature control signal based on a monitor result given by the monitor unit 30 and supplies this temperature control signal to the wafer prober 12 through the control cable 31.
Next, the probing card 21 and the chuck 22 will be described in detail.
As shown in
The heat transfer block 41 is axially divided into two parts. The upper part of the heat transfer block 41 provides a contact member 42 and the lower part thereof, a support bench 43. The contact member 42 and the support bench 43 are replaceable. The contact member 42 can be removed from the support bench 43 by, for example, suction force.
The contact member 42 is preferably made of a high-resistance material having excellent heat conduction, for example, a ceramic such as an alumina oxide. In this case, the temperatures of the heat transfer block 41 and the chuck 22 are readily adjusted to a predetermined testing temperature, while the probing pin 26 is prevented from short-circuiting with the contact member 42 when it has come in contact therewith. The contact member 42 may be made of metal hardened and insulated. In this case, the contact member 42 is suppressed from being deteriorated. Preferably the upper surface of the contact member 42 is substantially at the same level as that of the chuck 22.
The support bench 43 is provided, on a bottom thereof, with a pressure absorber 44 for holding a pressure of contact between the contact member 42 and the probing pin 26 to a substantially constant value. The pressure absorber 44 has a displacement mechanism of a hydraulic type by use of an oil pressure or an air pressure or of a spring type. The pressure absorber 44 displaces the heat transfer block 41 in accordance with a fluctuation of a contact pressure between the contact member 42 and the probing pin 26. In such a manner, the contact member 42 is brought into contact with the probing pin 26 stably. The pressure absorber 44 absorbs a load of about 1 kg through several kilograms corresponding to that of, for example, from several to several hundreds of the probing pins 26. The support bench 43 is fixed to a pedestal (not shown) which carries the chuck 22 via the pressure absorber 44. Therefore, the heat transfer block 41 moves integrally with the chuck 22.
The prober 12 includes a first camera 45 for measuring the position (height) of the upper surface of the chuck 22 (wafer W) or the heat transfer block 41. The first camera 45 is fixed to the frame of the wafer prober 12. The first camera 45 supplies image data to the chuck controller 20. The chuck controller 20 recognizes that the chuck 22 (wafer W) or the heat transfer block 41 is placed at a reference position when the upper surface of the chuck 22 (wafer W) or the heat transfer block 41 is aligned with the focus of the first camera 45.
The prober 12 includes also a second camera 46 for measuring the position (height) of the tip of the probing pin 26. The second camera 46 is fixed to the frame of the wafer prober 12. The second camera 46 supplies image data to the chuck controller 20. The chuck controller 20 recognizes that the probing pin 26 (probing card 21) is placed at a reference position when the tip of the probing pin 26 is aligned with the focus of the second camera 46.
After the chuck 22 (wafer W) or the heat transfer block 41 is placed in the reference position and the probing pin 26 is placed in the reference position, the chuck controller 20 aligns the upper surface of the chuck 22 (wafer W) or the heat transfer block 41 and the tip of the probing pin 26 with each other. That is, the chuck controller 20 moves the chuck 22 and the heat transfer block 41 so that the upper surface of the chuck 22 (wafer W) or the heat transfer block 41 may come in contact with the tip of the probing pin 26 at the predetermined pressure.
As shown in
As shown in
The following will describe a method for testing a semiconductor with reference to
Prior to testing, the heat transfer block 41 and the wafer W are held at the predetermined temperature. In step S11, the second camera 46 measures the position of the tip of the probing pin 26. In step S12, the first camera 45 measures the position of the upper surface of the heat transfer block 41.
The chuck controller 20 aligns the upper surface of the heat transfer block 41 and the tip of the probing pin 26 with each other. That is, as shown in
Step S13 continues until a warp or an elongation of the probing card 21 is maximized. An influence of the elongation or shortening of the probing pin 26 owing to a temperature variation is accommodated by the pressure absorber 44, so that the probing pin 26 comes in contact with the contact member 42 stably.
In step S14, when the temperature of the probing pin 26 reaches the testing temperature, the position of the tip of the probing pin 26 is measured by the second camera 46. In step S15, the position of the upper surface of the wafer W is measured by the first camera 45.
In step S16, the chuck controller 20 aligns the upper surface of the wafer W and the tip of the probing pin 26 with each other. That is, as shown in
The first embodiment has the following advantages.
(1) The probing pin 26 is directly heated or cooled by contact with the heat transfer block 41 and so its temperature is adjusted to the testing temperature which is substantially equal to the temperature of the wafer W. Accordingly, even when the probing pin 26 is brought into contact with the wafer W during the testing, the temperature of the probing pin 26 does not vary. Therefore, the probing pin 26 stays in contact with the wafer W at a stable pressure over a time lapse of from the early stage of the test (testing of the first electronic circuit on the wafer W) to the final stage of the test (testing of the last electronic circuit on the wafer W), so that the wafer can be tested stably. Furthermore, since the tip of the probing pin 26 can be brought into contact with the predetermined contact point (electrode of the electronic circuit on the wafer W), slippage (scrubbing amount) can be suppressed and uniformed, thus decreasing damages inflicted on the electrodes of the wafer W.
Since heat is transferred between the probing pin 26 and the heat transfer block 41 through direct contact, time is reduced as measured from a moment when the probing pin 26 is heated to the testing temperature to a moment when it is stabilized. Since no temperature setting heater is built in the probing card 21, noise due to a heater current does not occur.
(2) A fluctuation of a contact pressure between the heat transfer block 41 and the probing pin 26 is absorbed by the pressure absorber 44. Therefore, the probing pin 26 is prevented from being deformed by an excessive pressure when it is brought into contact with the heat transfer block 41. Furthermore, poor contact is prevented from occurring between the probing pin 26 and the heat transfer block 41, so that it does not take long time for the probing pin 26 to be heated to the testing temperature. In particular, it is possible to cope with a variation in pressure of contact corresponding to the number of the probing pins 26.
(3) The pressure absorber 44 which displaces the heat transfer block 41 in accordance with a fluctuation of a contact pressure of the probing pin 26 has a very simple displacement mechanism of a spring type or a hydraulic type. Therefore, increase in the costs for equipment is suppressed.
(4) Since the contact member 42 is made of an insulating material, the probing pins can be prevented from short-circuiting with each other through the contact member 42.
(5) Since the contact member 42 is made of a ceramic excellent in heat conduction, the temperature of the heat transfer block 41 can be readily adjusted to a predetermined testing temperature.
(6) Since the contact member 42 can be removed alone and replaced, the heat transfer block 41 can be maintained and repaired easily.
(7) A chuck heater 51 is provided also to a conventional chuck 90. The temperature setting element of the heat transfer block 41 is formed by extending the chuck heater 51 and the chuck cooling unit 54 thus suppressing increase in the costs of the equipment.
The following will describe a testing apparatus according to a second embodiment of the present invention with reference to FIG. 10. The second embodiment employs a contact member 56 made of a conductive gold plate. A pair of probing pins 26 are brought into contact with the contact member 56 to be made conductive with each other.
According to the second embodiment, the main controller 13 drives the probing card 21 to make conductive the pairs of the probing pins 26 in a predetermined order. The controller 13 serially transfers (in GP-IB communication etc.) to the measuring instrument 14 through the output cable 25 from the probing card 21 such data as to correspond to the resistance (contact resistance) of the probing pins 26 thus made conductive. Based on the data transferred to the measuring instrument 14, the main controller 13 can measure the resistance of each of the probing pins 26 to decide whether, for example, maintenance and repair are necessary.
To describe in detail, during testing or prior to it, the chuck controller 20 drives the chuck 22 and the heat transfer block 41 to bring the contact member 56 into contact with the probing pin 26. Then, a signal indicating the completion of the contact between the probing pin 26 and the contact member 56 is supplied through the control cable 23 to the main controller 13. When having confirmed this contact, the main controller 13 drives the probing card 21 through the probing card control cable 24 to make conductive the pairs of the probing pins 26 in the predetermined order, thus measuring the contact resistance thereof. The main controller 13 notifies the chuck controller 20 of the completion of contact resistance measurement through the control cable 23. Thus, it is possible to measure the contact resistance of the probing pins 26 in a condition where the probing card 21 is mounted, thus deciding whether maintenance and repair thereof is necessary.
The second embodiment has the following advantages in addition to the advantages (1) to (3), (6) and (7) of the first embodiment.
(8) It is possible to detect the resistance of the probing pins 26 by way of the contact member 56 made of a conductive material, to decide whether, for example, the maintenance and repair of these probing pins 26 (probing card 21) are necessary.
(9) According to the second embodiment, the data corresponding to the resistance of each of the probing pins 26 is transferred serially, so that the probing pins 26 can all be checked for whether they need to be maintained or repaired.
(10) According to the second embodiment, the contact member 56 is made of a gold plate having extremely high conductivity. It is, therefore, possible to reduce to a minimum the influence of the contact member 56 exerted on the detection of the resistance (contact resistance) of the probing pins 26.
The following will describe a testing apparatus according to a third embodiment of the present invention with reference to FIG. 11.
The third embodiment employs a chuck 57 provided with a heat transfer block 58. The fan-shaped heat transfer block 58 is fitted into a notch 57a formed in a periphery of the chuck 57. The outer surface of the heat transfer block 58 continues with that of the chuck 57. Preferably the heat transfer block 58 is made of a high-resistance material excellent in, for example, heat conduction. The heat transfer block 58 can be removed from the chuck 57. The probing pin 26 is brought into contact with the upper surface of the heat transfer block 58 so that its temperature may be adjusted to the testing temperature.
The third embodiment has the following advantages in addition to the advantages (1), (4) and (5) of the first embodiment.
(11) According to the third embodiment, the heat transfer block 58 is provided at part of the chuck 57. Therefore, the heat transfer block 58 and the chuck 57 can be arranged in a relatively small space. The heat of the chuck 57 set to the testing temperature is transferred to the heat transfer block 58, the heat of which is in turn transferred to the probing pin 26. Therefore, the temperature setting element is simple.
(12) The heat transfer block 58 can be removed from the chuck 57 for replacement, so that they can be maintained and repaired easily.
It should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention.
In the first and second embodiments, the heat transfer block 41 may be brought into contact with the chuck 22 to transfer the heat of the chuck 22 directly to the heat transfer block 41. In this case, it may be possible to omit the heat transfer block 52 and the heat transfer block cooling unit 55 provided for heat exchange with the heat transfer block 41.
The heat transfer block 58 may be made of metal hardened and insulated so that it may be hardly deteriorated.
The heat transfer block 58 may be formed of a gold plate, which is conductive. In this case, the resistance of the probing pin 26 can be detected.
In the third embodiment, the heat transfer block 58 may be divided into upper and lower parts.
In the third embodiment, the heat transfer block 58 may be provided, on the bottom thereof, with the pressure absorber 44.
In each of the embodiments, the chuck controller 20 may be replaced by the main controller 13 to control the driving of the chucks 22 and 57. In this case, the chuck controller 20 is omitted.
Although in each of the embodiments, the main controller 13 controls measurement and the temperature controller 15 controls temperatures, either one of these may conduct control on both the measurement and the temperature.
The heater 51 and/or the cooling unit 54 for setting the temperature of the chucks 22 and 57 may be built in each of the chucks 22 and 57.
The heater 52 and/or the cooling unit 55 for setting the temperature of the heat transfer block 41 may be built in the support bench 43.
It is preferred that the time required to heat or cool the probing pin 26 to the testing temperature is measured in an experiment beforehand.
Therefore, the present examples and embodiments are to be considered as illustrative and not restrictive and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalence of the appended claims.
Patent | Priority | Assignee | Title |
10068814, | Sep 24 2015 | ROHM CO , LTD | Apparatus and method for evaluating semiconductor device comprising thermal image processing |
7355428, | Jan 14 2004 | DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT | Active thermal control system with miniature liquid-cooled temperature control device for electronic device testing |
7514941, | Mar 15 2006 | Raytheon Company | Method and apparatus for predicting the reliability of electronic systems |
7675306, | May 04 2007 | Polaris Innovations Limited | Prober apparatus and operating method therefor |
7812627, | Oct 15 2007 | Tokyo Electron Limited | Test device |
8212577, | Feb 23 2008 | Tokyo Electron Limited | Needle trace transfer member and probe apparatus |
9638719, | Mar 28 2013 | Tokyo Electron Limited | Probe device having cleaning mechanism for cleaning connection conductor |
Patent | Priority | Assignee | Title |
3963985, | Dec 12 1974 | International Business Machines Corporation | Probe device having probe heads and method of adjusting distances between probe heads |
5124639, | Nov 20 1990 | Freescale Semiconductor, Inc | Probe card apparatus having a heating element and process for using the same |
5325052, | Nov 30 1990 | Tokyo Electron Limited | Probe apparatus |
JP5152389, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Nov 27 2002 | HAMADA, MORIHIKO | Fujitsu Limited | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 013647 | /0134 | |
Jan 03 2003 | Fujitsu Limited | (assignment on the face of the patent) | / |
Date | Maintenance Fee Events |
Jun 22 2005 | ASPN: Payor Number Assigned. |
Dec 31 2007 | M1551: Payment of Maintenance Fee, 4th Year, Large Entity. |
Mar 05 2012 | REM: Maintenance Fee Reminder Mailed. |
Jul 20 2012 | EXP: Patent Expired for Failure to Pay Maintenance Fees. |
Date | Maintenance Schedule |
Jul 20 2007 | 4 years fee payment window open |
Jan 20 2008 | 6 months grace period start (w surcharge) |
Jul 20 2008 | patent expiry (for year 4) |
Jul 20 2010 | 2 years to revive unintentionally abandoned end. (for year 4) |
Jul 20 2011 | 8 years fee payment window open |
Jan 20 2012 | 6 months grace period start (w surcharge) |
Jul 20 2012 | patent expiry (for year 8) |
Jul 20 2014 | 2 years to revive unintentionally abandoned end. (for year 8) |
Jul 20 2015 | 12 years fee payment window open |
Jan 20 2016 | 6 months grace period start (w surcharge) |
Jul 20 2016 | patent expiry (for year 12) |
Jul 20 2018 | 2 years to revive unintentionally abandoned end. (for year 12) |